Technology of pulsed electric fields (PEF) could be an alternative preservation method of food liquids compared to traditional heat pasteurisation where the main purpose is to inactive pathogenic bacteria. The main problem of all novel technologies is their effectiveness in microbial inactivation. The idea of PEF treatment, description of our laboratory PEF generator, factors affecting microbial inactivation during PEF process and effectiveness of that method in food systems were described in the paper. It was concluded that the best effect of food preservation with the use of PEF is achieved upon applying a combination of methods, i.e. PEF and high hydrostatic pressure (HHP) and others (according to “hurdle theory”). Different studies indicate that pulsed electric fields could be a useful method in liquid food preservation especially in the context of good organoleptic and functional properties of final products. However, the main assessment criterion of that method is the sufficient improvement of microbiological safety especially in the context of spores inactivation.